The present invention, in some embodiments thereof, relates to microscopy and, more particularly, but not exclusively, microscopy based on changes induced by interaction of a substance with an optical beam.
Optical microscopy has succeeded to surpass the Abbe resolution limit (about 0.5λ) either by near field techniques [1], or by far field super-resolution (SR) techniques such as stimulated emission depletion (STED), photo-activated localization microscopy (PALM), stochastic optical reconstruction microscopy (STORM) saturable absorption (SAX), structured illumination, SR optical fluctuation imaging (SOFI), and quantum emitters microscopy [2-9]. Fluorescence based techniques are useful when functional groups can be reliably and selectively labeled.
Also known are methods which are free of fluorescent labeling. Wang and coworkers used ground state depletion of the charge carriers in graphene-like structures in transmission mode [10]. Nedosekin and coworkers use nonlinear photo thermal microscopy in fluid medium [11]. Fleischer and coworkers generalized the Abbe's theory of diffraction to include nonlinear propagation and resolution enhancement [12,13].